DETECTION OF UNsecured LOAD IN AUTOMATED VEHICLES

Description

[0001] The invention relates to a method for detecting an unsecured load in a vehicle, particularly an automated vehicle. Furthermore, the invention relates to a control unit, a computer program, and a machine-readable storage medium. State of the art

[0002] When transporting loads in vehicles, proper load securing is essential for road safety. In manual or driver-operated vehicles, load securing is performed by the driver. The driver assumes the responsibility of securing the load and monitoring the vehicle for loose loads. However, particularly in fully automated vehicles, there is no driver available to perform load securing and monitoring.

[0003] Methods for detecting unsecured loads are already known, which determine the load's center of gravity and track it over time. This makes it possible to determine whether the load's center of gravity changes over time and thus shifts the load within a loading space. Such a method can be used particularly for truck trailers or containers. The position of the center of gravity can be determined via articulation or via different loads on the wheels. However, such detection of an unsecured load requires a significant shift of the load within the loading space. A slight shift of the load can only be inadequately detected.

[0004] DE 10 2014 226108 A1 discloses a method for detecting an unsecured load in a motor vehicle. A monitoring device uses a position detection device to determine a first position data set correlating with the position of the load in the motor vehicle in a first measurement cycle before or during a journey of the motor vehicle. A second position data set correlating with the position of the load is determined by the position detection device in a subsequent second measurement cycle during the journey. A difference between the first position data set and the second position data set is determined, and if the determined difference meets a predetermined triggering criterion, a predetermined securing measure is initiated.

[0005] Further prior art is disclosed in DE 10 2017 212596 A1, DE 10 2018 115615 A1 and US 8 786 437 B2. Disclosure of the invention

[0006] The object underlying the invention can be seen in proposing a method for precisely detecting the movement of a transport item which is transported by an automated vehicle.

[0007] This object is achieved by means of the respective subject matter of the independent claims. Advantageous embodiments of the invention are the subject matter of the respective dependent subclaims.

[0008] According to one aspect of the invention, a method for detecting unsecured cargo in a vehicle is provided. The vehicle can preferably be configured as a fully automated vehicle. A control unit, which can be located on or off the vehicle, can be used to implement the method.

[0009] In one step, measurement data in the form of lateral and / or longitudinal accelerations determined by at least one acceleration sensor are received. Acceleration data is determined from the vehicle.

[0010] During a subsequent evaluation of the acceleration sensor data, a check is carried out to determine whether a limit value has been exceeded by the measured lateral or longitudinal acceleration. If the limit value is exceeded, a time interval is initiated to detect the unsecured load. This time interval can be initiated immediately or with a time delay.

[0011] Subsequently, measurement data determined by at least one sensor during the started time interval are received and derivatives of the received measurement data are calculated with respect to time.

[0012] For example, if the time derivative of the received measurement data exceeds a threshold, an event is counted. An unsecured load is detected when a minimum number of counted events is reached, which are counted during the started time interval.

[0013] This method enables reliable and sensitive detection of loose cargo in automated vehicles. This prevents individual false detections, which can be caused, for example, by individual potholes. Measuring the kinetic impulses of a cargo during a defined period or time interval thus prevents false positives.

[0014] The measurement data from an acceleration sensor can be used as an initial trigger for a need to check the load securing.

[0015] The detection of events during the time interval is no longer limited to the measurement data from the acceleration sensor. Various sensors, such as microphones, chassis displacement sensors, air suspension sensors, and the like, can be used to detect events during the time interval. During the activated time interval, the time derivatives of the received measurement data are used to trigger and count events. The time derivatives of the measurement data represent the differences between the measurement data from two consecutive points in time and correspond to a tangent slope of the measurement data plotted against time in a diagram at the respective point in time.

[0016] An event can be triggered by a movement of the load and registered based on measurement data from at least one sensor.

[0017] According to a further aspect of the invention, a control unit is provided, wherein the control unit is configured to execute the method. The control unit can be, for example, a vehicle-mounted control unit, a vehicle-external control unit, or a vehicle-external server unit, such as a cloud system.

[0018] Furthermore, according to one aspect of the invention, a computer program is provided which comprises instructions which, when the computer program is executed by a computer or a control device, cause the computer or a control device to carry out the method according to the invention.

[0019] According to a further aspect of the invention, a machine-readable storage medium is provided on which the computer program according to the invention is stored.

[0020] According to the BASt standard, the vehicle can be operated in an assisted, partially automated, highly automated and / or fully automated or driverless manner.

[0021] The vehicle can be, for example, a passenger car, a truck, a semi-trailer truck, a flatbed truck, a robotaxi, and the like. The vehicle is not limited to operation on roads. Rather, the vehicle can also be designed as a watercraft, an aircraft, such as a transport drone, and the like. According to the invention, the time interval when the limit value is exceeded by the lateral acceleration is determined with a starting time with a time offset of t 0 = b i a y and an end time of t end = 3 b i a y initiated.

[0022] Alternatively, if the limit value is exceeded by the longitudinal acceleration, the time interval is set to a starting time with a time offset of t 0 = l i a x and an end time of t end = 3 l i a x initiated.

[0023] The time offset of the starting point depends on the respective acceleration in the transverse or longitudinal direction and the dimensions of the vehicle's cargo space in the corresponding direction. Thus, the length of the cargo space is relevant for a determined longitudinal acceleration, and the width of the cargo space is relevant for a determined lateral acceleration of the load.

[0024] The cargo space can be located in the vehicle itself, such as in a trunk or a rear seat, in a structure on the vehicle, on a roof rack or roof box, in a trailer, in a semi-trailer and the like.

[0025] According to a further embodiment, the time derivatives of the measurement data are calculated by at least one differentiator. The differentiator can be implemented in hardware or software. The measurement data is fed to an input of the differentiator or the differentiator amplifier. An output of the differentiator then provides temporal changes or time derivatives of the measurement data. This measure allows events during the started time interval to be recorded in a technically simple manner.

[0026] According to a further embodiment, during the started time interval, measurement data is received from at least one acceleration sensor, sound sensor, sensor of an air suspension of the vehicle, microphone, and / or displacement sensor, for example, a displacement sensor of a wheel suspension of the vehicle. This allows a check of the load securing based on measurement data from different sensors. The method can thus be implemented using a wide variety of sensors.

[0027] According to a further embodiment, when the minimum number of counted events during the started time interval is reached, control commands are generated to issue a warning message. This measure allows a teleoperator of the vehicle or a vehicle fleet to be notified by the control unit if an unsecured or loose load has been detected in at least one vehicle.

[0028] The warning message can be transmitted using a communication connection. The communication connection can be based, for example, on a wireless transmission technology. In particular, the warning message can be sent using a WLAN, UMTS, GSM, 5G, and similar transmission standards.

[0029] According to a further embodiment, when the minimum number of counted events during the started time interval is reached, the vehicle is transferred to a safe state and / or vehicle dynamics are reduced. Depending on the vehicle design and the load, a reduction in vehicle dynamics may already be sufficient to ensure safe transport.

[0030] If the load is particularly fragile or has a high mass relative to the vehicle, and the load is not secured, it may be advantageous to bring the vehicle into a safe position to prevent it from becoming a hazard in traffic. This can be done by parking the vehicle at the side of the road or driving it to the nearest parking lot or rest area.

[0031] A vehicle with an unsecured load that has been brought to a safe condition can then be inspected. The loose load can be manually secured, allowing the vehicle to continue driving with the load.

[0032] In the following, preferred embodiments of the invention are explained in more detail using highly simplified schematic representations.

[0033] Here, Fig. 1 is a plan view of a vehicle with a cargo space to illustrate a method according to an embodiment, and Fig. 2 is a schematic flow diagram to illustrate the method according to an embodiment.

[0034] The Figur 1 shows a plan view of a vehicle 1 with a cargo space 2 to illustrate a method 4 according to an embodiment. The method 4 is described in the Figur 2 explained in more detail.

[0035] The vehicle 1 has a control unit 6, which can receive and evaluate measurement data from various sensors 8, 10, 12. For example, the vehicle 1 can have an acceleration sensor 8, whose measurement data can be used for an initial check of the load securing. The acceleration sensor 8 can be arranged, for example, in the chassis of the vehicle 1.

[0036] The cargo space of vehicle 1 contains, for example, a transported item or load 14. In the illustrated embodiment, the cargo space 2 is configured as a rear seat bench or a trunk of vehicle 1. Vehicle 1 can be configured as a fully automated vehicle according to the BASt standard and thus be operated without a driver.

[0037] Another sensor 10 can be designed, for example, as a microphone or an interior microphone. Furthermore, measurement data from sensors 12 designed as displacement sensors can be received by the control unit 6.

[0038] Control unit 6 can further establish a communication connection 16 to a teleoperator 18.

[0039] In the illustrated embodiment, the communication connection 16 can be configured as an LTE or WLAN connection. In particular, the communication connection 16 can be used to receive instructions or transmit warning messages.

[0040] In the Figur 2 A schematic flow diagram is shown to illustrate method 4 according to one embodiment. Method 4 serves to detect an unsecured load 14 in a vehicle 1 and can preferably be carried out by a control unit 6.

[0041] Essentially, method 4 can be divided into several sections. In the first section, a time interval is opened in which events are counted.

[0042] Based on the counted events collected during a second section, an unsecured or loose load 14 can be detected.

[0043] The third section of method 4 is configured to generate a response to a detected unsecured load 14. A response can be implemented, for example, in the form of a warning message and / or by transferring the vehicle 1 to a safe state.

[0044] In a first step 20, measurement data determined by at least one acceleration sensor 8 in the form of lateral accelerations a y and / or longitudinal accelerations a x received.

[0045] The measured data are compared with a predefined limit value by a limit value detection device 22. The limit value can be defined in advance during calibration.

[0046] If a limit value is exceeded by the measured lateral accelerations a y and / or longitudinal accelerations a x Within the framework of an event counting period, a time interval 24 is started to detect the unsecured load 14.

[0047] The limit value can be exceeded, for example, by an impact of the unsecured load 14 against the loading space 2 of the vehicle 1. The time interval 24 can have an immediate start time or a delayed start time t 0. Accordingly, the time interval 24 can have an adjusted end time t end have.

[0048] The start time t 0 and the end time t end can be calculated using the following formulas: t 0 = b i a y und t end = 3 b i a y , if the lateral acceleration a y has exceeded the limit. t 0 = l i a x und t end = 3 l i a x , if the longitudinal acceleration a x has exceeded the limit value. b i a loading space width of 2 and l i a length of the cargo space 2.

[0049] For example, in the middle of the event counting window or the time interval 24, the time at which a loose object or the load 14, with an applied lateral acceleration a y slip from a left to a right interior side of the cargo space 2 and hit the wall there.

[0050] During the started time interval 24, measurement data determined by at least one sensor 8, 10, 12 are received, and temporal changes or temporal derivatives 26, 28, 30 of the received measurement data are calculated. This can be implemented by several differentiator amplifiers 26, 28, 30, which are integrated, for example, into the control unit 6.

[0051] Each sensor 8, 10, 12 can have a separate differentiator amplifier 26, 28, 30, which transforms the corresponding measurement data into derivatives of the measurement data with respect to time.

[0052] Measurement data from multiple travel sensors 12 of the wheel suspension are evaluated. For example, each of the four wheel suspensions can have its own travel sensor 12. The respective travel sensors 12 can determine measurement data in the form of travels or distances d 1 , d 2 , d 3 , d 4 .

[0053] The at least one interior microphone 10 can determine measurement data in the form of sound signals, which are converted into sound pressure levels L p by a sound pressure level calculation 32.

[0054] The respective temporal measurement data are then derived 26, 28, 30 during the active time interval 24. By the derivation 26 of the lateral accelerations a y and / or longitudinal accelerations a x after a while a jerk occurs j y in the transverse direction and / or a jerk j x in the longitudinal direction.

[0055] Subsequently, the derivatives of the measured data are subjected to a threshold detection 34, 36, 38. If the derivatives of the received measured data exceed a threshold, an event is counted.

[0056] The counting of events can be done by an event counter 40, which is active during the time interval 24.

[0057] An unsecured load is detected when a minimum number of 42 counted events is reached, which are counted during the started time interval 24.

[0058] If an unsecured load is detected, a reaction 44 can be initiated by the control unit 6. For this purpose, the control unit 6 can generate control commands that generate a warning message or that can put the vehicle 1 into a safe state.

Claims

1. Method for detecting an unsecured load (14) in an, in particular automatically operable, vehicle (1), by means of a control unit (6), wherein - measurement data in the form of lateral accelerations and / or longitudinal accelerations of the vehicle (1) acquired by at least one acceleration sensor (8) are received, - a time interval (24) for detecting the unsecured load (14) is started when the measured lateral accelerations or longitudinal accelerations exceed a limit value, - during the started time interval (24), measurement data acquired by at least one sensor (8, 10, 12) are received and derivatives of the received measurement data with respect to time are calculated, - an event is counted when the derivatives of the received measurement data with respect to time exceed the one threshold value, - an unsecured load (14) is detected when a minimum number of counted events that are counted during the started time interval (24) is reached, wherein, when the lateral acceleration exceeds the limit value, the time interval (24) has a start time with a time offset of t 0 = b i a y and an end time of tend = 3 b i a y or, when the longitudinal acceleration exceeds the limit value, said time interval has a start time with a time offset of t 0 = l i a x and an end time of t end = 3 l i a x , wherein I is a length of a cargo compartment (2) and b is a width of the cargo compartment (2) of the vehicle (1).

2. Method according to Claim 1, wherein the derivatives of the measurement data with respect to time are calculated by means of at least one differentiator.

3. Method according to either of Claims 1 and 2, wherein measurement data from at least one acceleration sensor (8), sound sensor, microphone (10) and / or position sensor (12), for example a position sensor of a wheel suspension system of the vehicle (1), are received during the started time interval (24).

4. Method according to any of Claims 1 to 3, wherein control commands for issuing a warning message are generated when the minimum number of counted events that are counted during the started time interval (24) is reached.

5. Method according to any of Claims 1 to 4, wherein the vehicle (1) is transferred to a safe state and / or vehicle dynamics are reduced when the minimum number of counted events that are counted during the started time interval (24) is reached.

6. Control unit (6), wherein the control unit (6) is designed to carry out the method (4) according to any of Claims 1 to 5.

7. Computer program comprising instructions which, when the computer program is executed by a computer or a control unit (6), cause same to carry out the method (4) according to any of Claims 1 to 5.

8. Machine-readable storage medium on which the computer program according to Claim 7 is stored.